{
return rendered2Data === rendered2[ index ];
} );
}
/**
* Checks if the center point of a single emoji is empty.
*
* This is used to determine if the browser is rendering an emoji with a single data point
* correctly. The center point of an incorrectly rendered emoji will be empty. A correctly
* rendered emoji will have a non-zero value at the center point.
*
* This function may be serialized to run in a Worker. Therefore, it cannot refer to variables from the containing
* scope. Everything must be passed by parameters.
*
* @since 6.8.2
*
* @private
*
* @param {CanvasRenderingContext2D} context 2D Context.
* @param {string} emoji Emoji to test.
*
* @return {boolean} True if the center point is empty.
*/
function emojiRendersEmptyCenterPoint( context, emoji ) {
// Cleanup from previous test.
context.clearRect( 0, 0, context.canvas.width, context.canvas.height );
context.fillText( emoji, 0, 0 );
// Test if the center point (16, 16) is empty (0,0,0,0).
const centerPoint = context.getImageData(16, 16, 1, 1);
for ( let i = 0; i < centerPoint.data.length; i++ ) {
if ( centerPoint.data[ i ] !== 0 ) {
// Stop checking the moment it's known not to be empty.
return false;
}
}
return true;
}
/**
* Determines if the browser properly renders Emoji that Twemoji can supplement.
*
* This function may be serialized to run in a Worker. Therefore, it cannot refer to variables from the containing
* scope. Everything must be passed by parameters.
*
* @since 4.2.0
*
* @private
*
* @param {CanvasRenderingContext2D} context 2D Context.
* @param {string} type Whether to test for support of "flag" or "emoji".
* @param {Function} emojiSetsRenderIdentically Reference to emojiSetsRenderIdentically function, needed due to minification.
* @param {Function} emojiRendersEmptyCenterPoint Reference to emojiRendersEmptyCenterPoint function, needed due to minification.
*
* @return {boolean} True if the browser can render emoji, false if it cannot.
*/
function browserSupportsEmoji( context, type, emojiSetsRenderIdentically, emojiRendersEmptyCenterPoint ) {
let isIdentical;
switch ( type ) {
case 'flag':
/*
* Test for Transgender flag compatibility. Added in Unicode 13.
*
* To test for support, we try to render it, and compare the rendering to how it would look if
* the browser doesn't render it correctly (white flag emoji + transgender symbol).
*/
isIdentical = emojiSetsRenderIdentically(
context,
'\uD83C\uDFF3\uFE0F\u200D\u26A7\uFE0F', // as a zero-width joiner sequence
'\uD83C\uDFF3\uFE0F\u200B\u26A7\uFE0F' // separated by a zero-width space
);
if ( isIdentical ) {
return false;
}
/*
* Test for Sark flag compatibility. This is the least supported of the letter locale flags,
* so gives us an easy test for full support.
*
* To test for support, we try to render it, and compare the rendering to how it would look if
* the browser doesn't render it correctly ([C] + [Q]).
*/
isIdentical = emojiSetsRenderIdentically(
context,
'\uD83C\uDDE8\uD83C\uDDF6', // as the sequence of two code points
'\uD83C\uDDE8\u200B\uD83C\uDDF6' // as the two code points separated by a zero-width space
);
if ( isIdentical ) {
return false;
}
/*
* Test for English flag compatibility. England is a country in the United Kingdom, it
* does not have a two letter locale code but rather a five letter sub-division code.
*
* To test for support, we try to render it, and compare the rendering to how it would look if
* the browser doesn't render it correctly (black flag emoji + [G] + [B] + [E] + [N] + [G]).
*/
isIdentical = emojiSetsRenderIdentically(
context,
// as the flag sequence
'\uD83C\uDFF4\uDB40\uDC67\uDB40\uDC62\uDB40\uDC65\uDB40\uDC6E\uDB40\uDC67\uDB40\uDC7F',
// with each code point separated by a zero-width space
'\uD83C\uDFF4\u200B\uDB40\uDC67\u200B\uDB40\uDC62\u200B\uDB40\uDC65\u200B\uDB40\uDC6E\u200B\uDB40\uDC67\u200B\uDB40\uDC7F'
);
return ! isIdentical;
case 'emoji':
/*
* Is there a large, hairy, humanoid mythical creature living in the browser?
*
* To test for Emoji 17.0 support, try to render a new emoji: Hairy Creature.
*
* The hairy creature emoji is a single code point emoji. Testing for browser
* support required testing the center point of the emoji to see if it is empty.
*
* 0xD83E 0x1FAC8 (\uD83E\u1FAC8) == Hairy creature.
*
* When updating this test, please ensure that the emoji is either a single code point
* or switch to using the emojiSetsRenderIdentically function and testing with a zero-width
* joiner vs a zero-width space.
*/
const notSupported = emojiRendersEmptyCenterPoint( context, '\uD83E\u1FAC8' );
return ! notSupported;
}
return false;
}
/**
* Checks emoji support tests.
*
* This function may be serialized to run in a Worker. Therefore, it cannot refer to variables from the containing
* scope. Everything must be passed by parameters.
*
* @since 6.3.0
*
* @private
*
* @param {string[]} tests Tests.
* @param {Function} browserSupportsEmoji Reference to browserSupportsEmoji function, needed due to minification.
* @param {Function} emojiSetsRenderIdentically Reference to emojiSetsRenderIdentically function, needed due to minification.
* @param {Function} emojiRendersEmptyCenterPoint Reference to emojiRendersEmptyCenterPoint function, needed due to minification.
*
* @return {SupportTests} Support tests.
*/
function testEmojiSupports( tests, browserSupportsEmoji, emojiSetsRenderIdentically, emojiRendersEmptyCenterPoint ) {
let canvas;
if (
typeof WorkerGlobalScope !== 'undefined' &&
self instanceof WorkerGlobalScope
) {
canvas = new OffscreenCanvas( 300, 150 ); // Dimensions are default for HTMLCanvasElement.
} else {
canvas = document.createElement( 'canvas' );
}
const context = canvas.getContext( '2d', { willReadFrequently: true } );
/*
* Chrome on OS X added native emoji rendering in M41. Unfortunately,
* it doesn't work when the font is bolder than 500 weight. So, we
* check for bold rendering support to avoid invisible emoji in Chrome.
*/
context.textBaseline = 'top';
context.font = '600 32px Arial';
const supports = {};
tests.forEach( ( test ) => {
supports[ test ] = browserSupportsEmoji( context, test, emojiSetsRenderIdentically, emojiRendersEmptyCenterPoint );
} );
return supports;
}
/**
* Adds a script to the head of the document.
*
* @ignore
*
* @since 4.2.0
*
* @param {string} src The url where the script is located.
*
* @return {void}
*/
function addScript( src ) {
const script = document.createElement( 'script' );
script.src = src;
script.defer = true;
document.head.appendChild( script );
}
settings.supports = {
everything: true,
everythingExceptFlag: true
};
// Obtain the emoji support from the browser, async